1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-05-18 10:35:06 +00:00
serenity/Kernel/Devices/PCSpeaker.cpp
Andreas Kling 3cba2a8a78 Kernel: Add a beep() syscall that beeps the PC speaker.
Hook this up in Terminal so that the '\a' character generates a beep.
Finally emit an '\a' character in the shell line editing code when
backspacing at the start of the line.
2019-05-15 21:40:41 +02:00

20 lines
481 B
C++

#include <Kernel/Devices/PCSpeaker.h>
#include <Kernel/i8253.h>
#include <Kernel/IO.h>
#include <Kernel/i386.h>
void PCSpeaker::tone_on(int frequency)
{
IO::out8(PIT_CTL, TIMER2_SELECT | WRITE_WORD | MODE_SQUARE_WAVE);
word timer_reload = BASE_FREQUENCY / frequency;
IO::out8(TIMER2_CTL, LSB(timer_reload));
IO::out8(TIMER2_CTL, MSB(timer_reload));
IO::out8(0x61, IO::in8(0x61) | 3);
}
void PCSpeaker::tone_off()
{
IO::out8(0x61, IO::in8(0x61) & ~3);
}